[masterofcode]

I have a buddy who gave me some of his hand loaded 7.62x54r with .312 cal bullets (Hornady i think)
He shoots it out of his 91/30 and said it would be fine in mine (1942 Russian, nothing special). I've never slugged the bore (or any for that matter) and I've read that the Russian bores can range from .310 upward. I just want to check, is it safe to shoot the .312 cal bullets if I dont know the diameter of my bore?

From what i read it's likely that my 91/30 is .310 or more, If mine is .310 would it be ok shooting .312 out of it? Does that small difference matter?

Thanks

 

[gdmoody]

Welcome to The Firearms Forum. You can probably get away with shooting .312, but you are a braver man than I am shooting someone else's reloads.

 

[masterofcode]

Define probably Im assuming it shouldn't be enough difference that it could get stuck or something, right?

He has been reloading for decades and doing 54r for a few years so I trust his judgement, just wanted to make sure there wouldn't a problem with bore diameter.

 

[nmckenzie]

Mosin bores varied widely - or perhaps I should say wildly - depending upon arsenal, peacetime vs. frantic wartime manufacture etc., so to be on the safe side I'd suggest slugging the bore and make your own reloads using the appropriate diameter bullet.

Just a thought about using someone else's reloads even when you know the powder and projectile are to spec. Many years ago while competing with a Garand in a match back east a friend tossed a handfull of '06 reloads onto my shooting mat - thought he was doing me a favor in case I needed to take a few extra sighters. Chambered one of them - or nearly so - and the bolt didn't close 100%. With some effort I extracted/ejected the round and there was powder flying all over the place as the case went spinning out. The bullet was stuck in the rifling, not by much - it was easily popped out with my cleaning rod, but it sure ruined my day knowing his reloads were intermingled with my own. His rounds worked fine in his M1, but the bullet was seated too far out for mine. Spent the rest of the match as a spectator & spotter.

 

[jim brady]

That .312 is a bit of a puzzler. Most people reload that caliber with .308 to .310 diameter bullets. From my own reloading, .312 or .313 would be what I'd use in a .303 British or 7.7 Jap. If the bore of your rifle were to slug on the large size (.311 to .313), you would be approaching the potential problem of chamber size, where loading too large of a bullet would prevent the case neck from expanding to release the bullet from the case on firing.

I don't reload that caliber, so you can take this with a grain of salt. It is not a good idea to use someone else's reloads. Told this story before - but here goes again. Friend of mine (with many years of reloading experience) pestered me into shooting off a few of his .30 Carbine loads in my pristine Winchester M1 Carbine that I took to the range for the first time. I cranked off 2 shots when something flew past my face. His "super-dooper" reloads were loaded up way too hot and caused my once immaculate stock to break off a chunk of wood at the recoil lug. I just stopped shooting my Carbine, smiled and said 'Thank You'. It was MY fault for shooting someone else's reloads even though I knew better.

 

[nmckenzie]

I believe it's RCBS that includes two different diameter expanders in their 7.62x54mmR die sets.

 

[TCoggins]

Here's my opinion. Worth exactly what I charge. Slug your bore (mine is .312, and I use .312 jacketed bullets, and .314 cast lead bullets). That will determine if the .312 bullets are ok for your bore. From there, you can determine if the reloads are ok for your rifle. Personally, I only shoot my reloads in my guns. My reloads don't get used in other people's guns, nor do I shoot anyone else's reloads.

Just my opinion.

 

[soundguy]

I agree, without slugging you just dont know what you have.

Guessing, you could either be tossing a wrench down a hallway, or stuffing an elephant into an elevator.

 

[masterofcode]

Thanks for all the replies. I think I'll just give them back to him. Of course the next question is, how do you slug a bore? And is the diameter determined at the wall of the bore or on the rifling?

 

[Grizzley1]

To slug a bore you push a soft lead slug through the bore and measure it's diameter after it's been squeezed to bore size.

The measurement you are looking for is the groove diameter rather than the bore diameter. View attachment 118998

 

[drymag]

There are some other vids:

I used fishing weights. I cut my dowel into 5" lengths. I took some grease from my zirk gun.
My M91/30 bored to 313.5. I shoot 311 and 312 bullets. I have shot 308 factory ammo thru it as well.

 

[LDBennett]

In general M-N have bore larger than 0.310 inches with some as loose a 0.315+ inches. You will not know until you slug the barrel. Some even have 308 barrels from re-barreling in some off beat nations who used them for war. M-N are crude guns at best.

In the one I had I used reloads with the bullets for 303 Enfield which measure 0.312 inches even though the bore was larger than that. There was no other choice for jacketed bullet. The accuracy was only OK.

As for slugging the barrel, you use to be able to use fishing weights but here in California lead fishing weights are banned (lead in the water??) and the weight are steel which you CANNOT use to slug a barrel. Search the internet and you may find a lead source for slugging barrels.It may also be that your state allows lead sinkers (??).

I will not shoot others reloads....PERIOD!!!!!

LDBennett

 

[masterofcode]

Thanks again. I gave back his reloads. I'm going to start getting a workspace setup in my garage so I can start doing it myself after I slug the barrel. Somehow I think I found a new hobby.

 

[nmckenzie]

A note on one particular Mosin bore that has to do with quality, not measurements. We (dear one and I) have seven Mosins: one Russian, three Soviet, two Finns, and one Chinese - a Type 53 Carbine. After bringing the grease soaked '53 home I stripped it down for a thorough cleaning. Finished the bore, took a peek, and it seemed to have two different sets of lands and grooves, one running from the chamber and stopping abruptly midway up the bore, the next starting where the first left off and continuing out to the muzzle. Problem was that land and groove set No.1 didn't even come close to connecting with set No.2. Take a sheet of lined loose leaf paper, cut it in half vertically, then slide one half so its lines are between the lines on the other half. That's what this '53 bore would look like. No idea as to the how or why of this situation.

 

[LDBennett]

A note on one particular Mosin bore that has to do with quality, not measurements. We (dear one and I) have seven Mosins: one Russian, three Soviet, two Finns, and one Chinese - a Type 53 Carbine. After bringing the grease soaked '53 home I stripped it down for a thorough cleaning. Finished the bore, took a peek, and it seemed to have two different sets of lands and grooves, one running from the chamber and stopping abruptly midway up the bore, the next starting where the first left off and continuing out to the muzzle. Problem was that land and groove set No.1 didn't even come close to connecting with set No.2. Take a sheet of lined loose leaf paper, cut it in half vertically, then slide one half so its lines are between the lines on the other half. That's what this '53 bore would look like. No idea as to the how or why of this situation.

What do you expect from Russian/Eastern European hayseeds (Russian/Eastern European industrial workers) fresh off the farm even before farms were mechanized? I'll say it a again....M-N are crude at best. Mine is long gone!

How could any normal human being working in Quality Control think the above bore was acceptable?

LDBennett

 

[soundguy]

Wow, talk about swagging and shaving!!

 

[ricochet rabbit]

I bought a box of 32 caliber soft lead balls, cut a quarter inch dowel rod into 6 inch pieces. Oiled the bore well, and lubed the ball and put it into the bore and tapped it in with a mallet, then using the mallet pushed it through the bore with the dowel rods. Ball dropped out of the chamber and I used a caliper to measure the groove diameter. Turns out both of my Mosins are .312.

 

[Kweeksdraw]

A note on one particular Mosin bore that has to do with quality, not measurements. We (dear one and I) have seven Mosins: one Russian, three Soviet, two Finns, and one Chinese - a Type 53 Carbine. After bringing the grease soaked '53 home I stripped it down for a thorough cleaning. Finished the bore, took a peek, and it seemed to have two different sets of lands and grooves, one running from the chamber and stopping abruptly midway up the bore, the next starting where the first left off and continuing out to the muzzle. Problem was that land and groove set No.1 didn't even come close to connecting with set No.2. Take a sheet of lined loose leaf paper, cut it in half vertically, then slide one half so its lines are between the lines on the other half. That's what this '53 bore would look like. No idea as to the how or why of this situation.

Mac maybe it had a bore obstruction shot out of it. I have heard it was common in
Europe to do so. And when I was a kid it was somewhat common in the US. When you push a patch through it is it looser in fit at the disrupted rifling? Usually the barrel is bulged and the rifling does not match. I understand the bulge but not the disrupted rifling. Sometimes they shoot ok like that, and sometimes won't hit a barn at 50yds. I have a Carcano like that. It shoots ok. The Mosin barrel may be so heavy and tough that it just did not bulge. Or what LD said, laborers just had a bad day.

 

[masterofcode]

Hey everyone thanks for the help. I slugged my bore using some lead bullet shaped fishing weights. Looks like the groove diameter is .314 and the bore diameter is .303. Has anyone had good success with reloading 7.62x54r? When I gave back the bullets my buddy gave me a bottle of IMR 4064 which he says works well, so I now have powder. I'm looking to get the equipment later this week and I cleared some space in my garage.
Also from what I can tell the cheapest way to get brass right now is to buy the Winchester stuff and shoot it. Are there any good sources for brass?

 

[nmckenzie]

From what I've read about the Type 53s some Soviet made parts - both new and surplus - were utilized in at least the initial production batches, thus helping to get Mao's small arms industry off the ground. I do know the cartridge follower of this particular '53 saw service in the USSR because some conscript scratched what I presume to be his name (in Cyrillic) onto the upper surface. The barrel isn't bulged, so I guess it's possible that some enterprising Soviet arsenal manager decided to empty his pile of reject and OOPS! parts and unload them on the Chinese.